BY STEVEN DiMARTINO
The areas of low pressure that produced moderate to heavy rain over the Philadelphia and New York City metropolitan areas yesterday, have now converged into one powerful low pressure system over western Lake Erie this morning. This low pressure system is driving a cold front through the region this morning with widely scattered showers, heavy at times.
Note the lines on the surface map. These lines are lines of uniform pressure. The tighter the lines, the stronger the pressure gradient and the stronger the pressure gradient, the stronger sustained winds will be. As the atmosphere begins to mix later this morning and this afternoon, strong winds from the mid levels combined with this pressure gradient will produce windy conditions with sustained winds of 10 to 20 mph with higher gusts up to 45 mph possible. While the winds will be an issue, especially for high profile vehicles, the good news is that these winds will be ushering in dry air. Clouds will start to clear out this afternoon and evening while dew points will continue to crash. Temperatures this morning will be the warmest of the day for many locations before the cold front moves through, thereafter temperatures will fall slightly and then remain steady with high temperatures in the mid to upper 60's for most locations.